Managing Log Retention in Multitarget Replication Environments

Log Retention Settings

In accordance with the SAP HANA documentation, if a primary system is replicating to more than one secondary system, force log retention and log retention propagation should be used to reach an optimized re-sync and avoid a full datashipping after takeover or other disconnect situations.

From the SAP HANA help documentation:

If enable_log_retention = force_on_takeover is configured, the log will be retained during replication for all direct secondaries until a takeover is executed. During takeover, the parameter is set to force. This means the log will be retained independently of any secondary system. The configuration must be done manually (for example, by the administrator or using setup scripts) because the SAP HANA system doesn’t know when the system landscape has been completely reconfigured.

!LifeKeeper for Linux does not automatically manage these parameters, so they should be updated manually by an administrator after takeover or successful re-registration of the entire system landscape. See the SAP HANA System Replication Guide for more details about the enable_log_retention and propagate_log_retention parameters.